1. spontaneous symmetry
breaking

2. symmetry: rotation

3. spontaneous symmetry breaking

4. symmetrry breaking in field theory
spontaneous
symmetrry breaking in field theory

5. Anderson

6. Peter Higgs

7. Kibble Guralnik Hagen Englert Brout

8. example 1:
real
scalar field

11. self - interaction:

15. => 2 ground states

17. example 2:
complex scalar field

20. 2

22. gauge theory
gauge group: U(1)

26. Before symmetry breaking: massless gauge boson, (2 polarizations) 2 massive scalars
Degrees of freedom:

27. After symmetry breaking: one massive gauge boson + one scalar

29. one scalar 
„Goldstone – boson“
absorbed by the
gauge boson
mass generation

30. gauge theory
gauge group: SU(2)
scalars: doublet

34. 3 scalars absorbed
by 3 gauge bosons
one scalar remains
( Higgs boson)

35. gauge theory
gauge group: SU(2)
scalars: triplet